What is Asbestos?
Asbestos is the name applied to a group of six naturally occurring fibrous minerals (chrysotile, amosite, crocidolite, plus the fibrous varieties of actinolite, tremolite, and anthophyllite) of asbestos fibres. Non asbestos (non fibrous) forms of tremolite, actinolite, and anthophyllite also are found in nature.
The most common mineral types are white (chrysotile), blue (crocidolite) or brown (amosite). Asbestos can be found naturally in the earth in some parts of Australia. For example, in Australia blue asbestos deposits were mined at Wittenoom, W.A. and white asbestos at Woodsreef, N.S.W.
|Exposed woven asbestos fuse lining inside a fuse holder||Asbestos cement simulated plank wall cladding|
Asbestos fibres were once valued for their resistance to heat and most chemicals plus their high tensile strength. Hence asbestos fibres have been mined for use in a wide range of man-made products, mostly in building materials, friction products, and heat-resistant materials.
Therefore materials containing asbestos can be found almost anywhere. Asbestos fibres do not evaporate into air or dissolve in water. Small fibres and fibre-containing particles may remain suspended in the air for a long time and can be carried long distances by wind or water currents before settling. This means building containing a large amount of asbestos, even after removal works may still contain dangerous amounts of asbestos carried by internal air movement in cavities and inaccessible areas.
|Asbestos rope on the exhaust of a back- up generator||Woven asbestos used on airconditioning pipework mounts|
In indoor air, the concentration of asbestos depends on whether asbestos was used for insulation, ceiling or wall linings, or other purposes, and whether these asbestos-containing materials are in good condition or are deteriorated and therefore easily crumbled (known as its friability.)
Diseases recognised as caused by asbestos include lung cancer, asbestosis, mesothelioma and pleural plaques. All area as a result of inhalation of asbestos fibres. Other diseases and cancers are suspected to be caused by or linked to asbestos however further research is required.